What do Brain Injuries Tell us about Free Will?

When a family member sustains a traumatic brain injury (TBI), panic sets in as they fight for their life. These injuries can be sustained as a result of a vehicle accident, a fall, a stroke, an assault, carbon monoxide poisoning, or meningitis. For some families, their child, their sibling, their spouse, will never quite be the same in behavior or temperament. This however manifests itself in varying degrees of intensity ranging from a shorter temper and frequent impulsive purchases, to daily aggressive outbursts, and extreme antisocial behavior.

These changes in behavior are caused by damage to areas such as the frontal and temporal lobes, the amygdala and the hippocampus which can lead to volatile emotions, impaired decision making and problem-solving skills, memory impairment, physical aggression, and impulsivity. Brain injuries introduce a whole host of issues into a person’s life, each of which can contribute to depression, OCD, or PTSD. These changes give rise to an unpredictability that has led to childhood brain injuries being cited as a risk factor for criminal activity later in life.

“WITH A DISPROPORTIONATE NUMBER OF THE INCARCERATED POPULATION LIVING WITH A BRAIN INJURY RELATIVE TO THE GENERAL POPULATION, IT IS DIFFICULT TO DENY THAT A RELATIONSHIP EXISTS BETWEEN BRAIN INJURY AND CRIMINALITY.”

With a disproportionate number of the incarcerated population living with a brain injury relative to the general population, it is difficult to deny that a relationship exists between brain injury and criminality. Since 1966, the association between brain injury and criminal behaviour has been in the public consciousness, with the discovery of a brain tumour in the amygdala of Charles Whitman, the man who committed one of America’s worst mass school shootings. Questions were asked whether it was Whitman’s personality or his tumour that caused him to commit the crime. Studies have since been carried out in an effort to more definitively ascertain whether the link between criminal behaviour and brain malformations is strong enough to lay the blame for such crimes beyond the control of their perpetrator.

Free will is, by definition, the power of acting without the constraint of necessity or fate; it is the ability to act at one’s own discretion. A person with a brain injury struggles with weighing up all options and then making an informed decision, having a diminished capacity to problem-solve as a result of their injuries, causing them to act on impulse. To some extent, we all know what it is like to experience diminished free will. Oftentimes our decisions are affected by the thoughts of societal expectations that govern our daily life. Concern about how we are perceived and how the things we say or do implicate us in different situations are all factors that heavily influence the decision-making processes of many individuals.

Those with brain injuries however, do not have the capacity to weigh up these options and so react as a direct result of their impulsive emotions. While in the case of Charles Whitman this had catastrophic consequences resulting in massive loss of life, perhaps Whitman’s actual personality is responsible for some of the actions he has taken. From this we could deduce that along with his brain tumor, Whitman was, in short, a bad person.

After all, there are millions of people with brain injuries who do not commit mass murders or other major crimes. Maybe it is more reasonable to conclude that certain people are already on the brink of carrying out such behaviours, and that for them, a TBI is just the straw that may break the camel’s back. Perhaps we should all be worried about how tenuous our free will is, how open it is to being meddled with by forces beyond our control.

Take a type of influence that is familiar to all of us: social pressure. The pressure to conform, to orient ourselves using a compass directed primarily by fear of what our neighbours would say, could easily be said to chip away somewhat at our freedom of will. Even a short moment of reflection upon our own life experiences should bring to mind some instances where our own core values took second place behind the norms of society. Were we free to choose how to act in those instances? Was our freedom prevented, or merely weakened? These questions become all the more salient when we consider the actions of Charles Whitman and those like him.

Are brain injuries a different case, though? Given what we know about the brain-behaviour relationship, it seems reasonable to conclude that they are just another form of pressure. Whatever degree of freedom we attribute to individuals who have been compromised by social forces, something like that should also be attributed to those who have been compromised by their neuroanatomy. It appears that brain injury may just be a special, albeit vivid, case of influence on our free will.